Researchers in South Korea (alongside U.S. collaborators) have developed a surgical device that works like a glue gun to 3D-print biodegradable bone grafts directly into fractures or bone defects during surgery. This approach sidesteps many limitations of prefabricated grafts, namely the time, preparation, modeling, and trimming required to make them fit irregular or complex bone defects, tells this article on NewAtlas.com.
The printing material is a composite made from polycaprolactone (PCL), a biodegradable polymer, and hydroxyapatite (HA), a mineral naturally found in bone. These “glue sticks” melt at a low temperature (safe for living tissue), extruding through the modified glue gun to form a scaffold that conforms to the shape of the defect. The researchers also tuned the molecular weight of PCL and the ratio of HA to adjust strength, elasticity, degradation rate, and adhesion to the surrounding bone.
Antibiotics (vancomycin and gentamicin) can be incorporated into the graft material. That builds in protection against infection without needing systemic doses. In lab trials, the composite passed tests of strength, bending, degradation under simulated physiological conditions, and biocompatibility (mouse pre-osteoblasts, human bone marrow stem cells).
In animal tests (rabbit femoral bone defect models too large to heal naturally), the printed grafts outperformed traditional bone cement over a 12-week period. Micro-CT scans showed stronger, more natural bone growth, better cortical thickness, and favorable structural metrics. The material also degraded gradually, making room for new natural bone.
There were no signs of adverse inflammation or tissue damage. However, the study notes that by 12 weeks, the defects were not fully filled. More work remains: sterilization, regulatory clearance, further trials in larger animals, and manufacturing consistency.
Overall, this proof-of-concept shows promise: surgeons might soon have a tool to print personalized bone grafts in the OR, matching the unique shape of defects and reducing delays and costs involved in current methods.
The device prints a mixture of polycaprolactone (PCL), a biodegradable polymer, and hydroxyapatite, a mineral naturally found in bone. The printing is done at a low temperature to avoid damaging surrounding tissue. The scaffold is designed not only to support bone repair but also to degrade gradually, letting new bone tissue replace it over time.
An additional feature: the material can be doped with antibiotics such as vancomycin or gentamycin. This addition could reduce infections and the need for systemic antibiotic treatment, potentially lowering the risk of resistance.
In comparative tests over 12 weeks, the printed grafts outperformed conventional bone cement in several structural metrics, including stronger tissue formation, more natural bone structure, greater cortical thickness, and better mechanical properties (e.g., polar moment of inertia). There were no signs of inflammation or tissue damage around the grafts.
Despite promising results, the technology isn’t ready for clinical use yet. The team must work out sterilization protocols, conduct further pre-clinical trials, and standardize the manufacturing process to ensure consistent performance.
This 3D printing gun could transform bone repair by making grafting more precise, adaptable, and biologically compatible. It may reduce the gap between what surgeons can plan and what they can execute inside the body.